topic UnboundLocalError using sequence in Python Questions

UnboundLocalError using sequence

StevenCross — Wed, 27 Jan 2021 21:01:15 GMT

Hello all,

I have a script where I am parsing through all the MXD's on the server and getting the service properties of all the feature classes and writing to a csv file.

I am running into an issue in an else statement where it is UnboundLocalError: local variable 'db' referenced before assignment.

I have tried changing the indentation of the sequence and when I put that inside the else statement I only get the first MXD in the folder written to the csv.

Below is the script. Any help would be appreciated.

import arcpy, os, csv, socket #Turn off ESRI geoprocessing logging so XML column does not fill up arcpy.SetLogHistory(False) arcpy.gp.overwriteOutput = True ags = socket.gethostname() print "ArcGISServer:" + ags def main(folder, outputfile): with open(outputfile, "wb") as f: w = csv.writer(f) header = ("MapDocument", "LayerName", "FeatureClass", "Database", "Server", "Version", "UserName", "Authentication", "ArcGISServer") w.writerow(header) rows = crawlmxds(folder) w.writerows(rows) def crawlmxds(folder): for root, dirs, files in os.walk(folder): for f in files: if f.lower().endswith(".mxd"): mxdName = os.path.splitext(f)[0] mxdPath = os.path.join(root, f) mxd = arcpy.mapping.MapDocument(mxdPath) print mxdPath print mxdName for lyr in arcpy.mapping.ListLayers(mxd): if lyr.supports("DATASOURCE"): dSource = str(lyr.dataSource) if '.sde' in dSource: fcName = dSource.split('.sde\\') print "Layer Name: " + lyr.name print "Feature Class: " + fcName[1] elif '.gdb' in dSource: fcName = dSource.split('.gdb\\') print "Layer Name: " + lyr.name print "Feature Class: " + fcName[1] ## if lyr.supports("definitionQuery"): ## dq = lyr.definitionQuery ## print "Definition Query: " + lyr.definitionQuery ## else: ## print "NA" if lyr.supports("SERVICEPROPERTIES"): if lyr.serviceProperties["ServiceType"] != "SDE": print "Service Type: " + lyr.serviceProperties.get('ServiceType', 'N/A') print " URL: " + lyr.serviceProperties.get('URL', 'N/A') print " Connection: " + lyr.serviceProperties.get('Connection','N/A') print " Server: " + lyr.serviceProperties.get('Server','N/A') print " Cache: " + lyr.serviceProperties.get('Cache','N/A') print " User Name: " + lyr.serviceProperties.get('UserName','N/A') print " Password: " + lyr.serviceProperties.get('Password','N/A') print "" else: print "Service Type: " + lyr.serviceProperties.get('Service Type', 'N/A') db = lyr.serviceProperties.get('Database', 'N/A') print " Database: " + lyr.serviceProperties.get('Database', 'N/A') svr = lyr.serviceProperties.get('Server', 'N/A') print " Server: " + lyr.serviceProperties.get('Server', 'N/A') srvc = lyr.serviceProperties.get('Service', 'N/A') print " Service: " + lyr.serviceProperties.get('Service', 'N/A') ver = lyr.serviceProperties.get('Version', 'N/A') print " Version: " + lyr.serviceProperties.get('Version', 'N/A') un = lyr.serviceProperties.get('UserName', 'N/A') print " User Name: " + lyr.serviceProperties.get('UserName', 'N/A') auth = lyr.serviceProperties.get('Authentication', 'N/A') print " Authentication: " + lyr.serviceProperties.get('Authentication', 'N/A') print "" seq = (mxdName, lyr.name, fcName[1], db, svr, ver, un, auth, ags); yield seq del mxd if __name__ == "__main__": folderPath = r"mxdpath" # or arcpy.GetParameterAsText(0) output = r"csvpath" # or arcpy.GetParameterAsText(1) main(folderPath, output)

Re: UnboundLocalError using sequence

DavidPike — Wed, 27 Jan 2021 21:12:38 GMT

Just glanced through, but you've not created the variables (db, svr...) to yield when the condition is met (not SDE) - only when SDE. A quick fix might be to assign them within that if true block - db = "None" ... etc.

Far from a coding whizz so take a big pinch of salt with that.

Re: UnboundLocalError using sequence

DanPatterson — Wed, 27 Jan 2021 21:45:45 GMT

the variable/property "db" only gets a value in one case.

A safe way of finding out what is going on is to assign potential returns to some value, whether it be None prior to running any loops. For example

db = None; svr =None; ver = None; un = None; auth = None; ags = None

db = None; svr =None; ver = None; un = None; auth = None; ags = None def crawlmxds(seq): for i in seq: print("{}".format(i)) seq = [db, svr, ver, un, auth, ags] crawlmxds(seq) None None None None None None

Then when you see a None, you know something is wrong.

The alternative is check each variable assignment before you try to use it, as is your current case.

Re: UnboundLocalError using sequence

StevenCross — Wed, 27 Jan 2021 23:53:55 GMT

Thanks Dan and David! I took a look at both of your suggestions and what think I may have found a solution...however not the prettiest or most understandable but if I put the variables after the Service Type variable like below it works.

if lyr.supports("SERVICEPROPERTIES"): if lyr.serviceProperties["ServiceType"] != "SDE": db = lyr.serviceProperties.get('Database', 'N/A') print " Database: " + lyr.serviceProperties.get('Database', 'N/A') svr = lyr.serviceProperties.get('Server', 'N/A') print " Server: " + lyr.serviceProperties.get('Server', 'N/A') srvc = lyr.serviceProperties.get('Service', 'N/A') print " Service: " + lyr.serviceProperties.get('Service', 'N/A') ver = lyr.serviceProperties.get('Version', 'N/A') print " Version: " + lyr.serviceProperties.get('Version', 'N/A') un = lyr.serviceProperties.get('UserName', 'N/A') print " User Name: " + lyr.serviceProperties.get('UserName', 'N/A') auth = lyr.serviceProperties.get('Authentication', 'N/A') print " Authentication: " + lyr.serviceProperties.get('Authentication', 'N/A') print "Service Type: " + lyr.serviceProperties.get('ServiceType', 'N/A') print " URL: " + lyr.serviceProperties.get('URL', 'N/A') print " Connection: " + lyr.serviceProperties.get('Connection','N/A') print " Server: " + lyr.serviceProperties.get('Server','N/A') print " Cache: " + lyr.serviceProperties.get('Cache','N/A') print " User Name: " + lyr.serviceProperties.get('UserName','N/A') print " Password: " + lyr.serviceProperties.get('Password','N/A') print "" else: print "" seq = (mxdName, lyr.name, fcName[1], db, svr, ver, un, auth, ags); yield seq